Servicing
5
Installation and servicing instructions condensing gas boiler 800 - 24/29/43/60 and 800 - 24T25/29T25 H/V • edition 02/2006
51
Subject to modifications resulting from technical improvements !
Buderus • http://buderus-domestic.co.uk
5.3.10 Replacing the flow, return and safety sensors
z
Close maintenance isolating valves.
z
Drain the 800 Series.
z
Unplug.
z
Unscrew sensor and replace with new unit.
z
Plug in cable connection.
z
Open maintenance isolating valves.
Table 10 Resistance values (indicative values) of the sensors
fig. 67 Replacing the flow/return sensors
fig. 68 Boiler temperature sensor diagram
Boiler temperature sensor
(˚C)
R (
Ω
)
40
50
60
70
80
90
0
0
10
20
30
10,000
5,000
15,000
NOTE
Fill the 800 Series and purge the system of air.
Temperature
in °C
Resistance
in
Ω
Temperature
in °C
Resistanc
e in
Ω
0
29,490
5
23,462
55
3,271
10
18,787
60
2,760
15
15,136
65
2,339
20
12,268
70
1,990
25
10,000
75
1,700
30
8,197
80
1,458
35
6,754
85
1,255
40
5,594
90
1,084
45
4,656
95
1,
940
50
3,893
100
1,
817
fig. 69 Outside temperature sensor diagram
Outside temperature sensor
(˚C)
R (
Ω
)
0
5
10
15
20
25
-20
-15
-10
-5
50,000
20,000
80,000
40,000
30,000
10,000
60,000
70,000
